I have an 8mm Mauser 98k, not sure what year made but it has a large 41 on the receiver which I seem to recall denotes the arsenal where it was made. It was a Soviet capture piece, by the reddish blackish shellac stuff on the stock and the peened-out stamps. I'm toying with reloading for it, and I'm interested in knowing how heavy a bullet I can load safely. As long as I can break 2000fps I'm not too concerned about pushing velocity with a heavy bullet, but it needs to be accurate. I've seen 220 grain bullets for sale... does anybody know if the twist in a 98k will stabilize a bullet that long?

__________________"... I cannot but conclude the bulk of your [politicians] to be the most pernicious race of little odious vermin that nature ever suffered to crawl upon the surface of the earth." ~ Jonathon Swift

The 8mm Mauser was designed for a 198 grain bullet in 1934, I doubt if a 220 grain bullet will give you trouble, but check your reloading manuals and see what they say. There's not much room in the case with a 200 grain bullet seated for correct length, so anything over 220 grain could give you some issues.

I'd get your Russian Capture checked out by a gunsmith first, and run some factory loads through it beforehand.

Oh, it seems to be safe, I've put many full-power surplus loads through it over the years, and the only thing that happens is holes in the target and bruises on my shoulder.

Wouldn't deviate from my manuals, of course, but just because it's in the manual that doesn't mean my rifle will stabilize it. :-)

Also, to clarify, I'm specifically concerned with the suitability of the twist rate and the appropriate throating to avoid overpressure conditions.

__________________"... I cannot but conclude the bulk of your [politicians] to be the most pernicious race of little odious vermin that nature ever suffered to crawl upon the surface of the earth." ~ Jonathon Swift

The original load for the 7.92x57 Mauser cartridge, adopted with the Commission rifle in 1888, was a 225-gr. round nose bullet

So the implication here being that the later carbine designs adhered to the same twist and throat specifications?

__________________"... I cannot but conclude the bulk of your [politicians] to be the most pernicious race of little odious vermin that nature ever suffered to crawl upon the surface of the earth." ~ Jonathon Swift

Agree on the heavier bullets. Most milsurps mausers were designed to fire 196 gr bullets.
196 & 200gr are my preference. 180 grainers are acceptable.
Never could get acceptable accuracy with 150 gr bullets.

150 grainers CAN work fine in a 1 in 9.45" (standard Mauser rifling rate) barrel. Those who haven't gotten them to work just haven't found the right load combination. I've shot tons of them, with very good accuracy.

As for heavy bullets, you can go as heavy as you wish - with one proviso. Be aware that, the heavier a bullet for a given diameter, the LONGER it is. At some point, you will run out of room, so to speak. That is, beyond a certain weight, you won't be able to chamber loaded rounds, unless the bullets are seated so deeply in the cases that gas blow-by and bullet base deformation becomes a problem. (And jambing the bullets into the rifling upon chambering, with anything but LIGHT loads and CAST bullets, is very dangerous.) The longest/ heaviest I've ever gotten to work in my Mausers has been approx. 215 grains. I know that you can go beyond this - somewhat. But, 235 grainers are too long for most Mausers (they certainly are for mine). So, the "limit" is somewhere between 215 and 235 grains, for most Mausers (if not all).

Really, you'd be better off with a bullet in the 175 to 200 grain range. You'll find the least difficulty in achieving a good load, if you stay within that range.

I vaguely remember a box of imported 8mm hunting ammo with 260 gr bullets. These were considered Bear and Elk loads. The European Elk is the cousin of the North American Moose.

PS
As I remember it the Commision rifle cartridge is the 8mmJ while the WW1 and later cartridge is the 7.92X57.
The American 8mm Mauser commercial cartridges were loaded with use in either the Gew 88 or Model 98 actioned rifles, and originally used .321 dia bullets.

The milspec 8mm barrel was .321 with .318 bullets expected to bump up, but many 8mmJ sporting rifles used .318 bores.
Some Gew 88 actioned sporting rifles have barrels marked for use with cast lead bullets only.

"Oddly enough, I just opened the October 2012 issue of Handloader magazine and found an article on reloading for the 7.92x57 Mauser.

Both test rifles are K98 Mauser actions - one is a sporter, while the other appears to be a military standard.

One load shown is for 250-grain Woodleigh Weldcore bullets, so it would appear that you can go up to that weight bullet in that action."

Good to know. By the way, simply to clarify, I did use the term "limit" in quotation marks. I certainly was not talking absolutes, but rather, practicality. Perhaps the Woodleigh bullets are made from a softer, denser alloy (and thus heavier for a given diameter and length). Or, perhaps they are intended to be seated really deeply in the cases. Being jacketed, they can be seated deeper without damage, but that is not the best way to get accuracy. I don't know. I'm sure that human ingenuity can solve the issue, one way or another. Nevertheless, I stand by my assertion that one is probably better off all 'round in staying with more "normal" bullet weights for the cartridge, with roughly 200 grains being "best". Just my opinion, though.

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